Recording apparatus

1 . A recording apparatus comprising:

a tank configured to store liquid to be supplied to a recording head that ejects the liquid, the tank including an inlet port for liquid injection;

a cap unit including a shaft portion and a cap configured to turn about the shaft portion between a first position at which the cap caps the inlet port and a second position at which the cap does not cap the inlet port, the shaft portion being provided to a housing that encloses the tank; and

a biasing unit configured to bias the cap unit in a direction to move the cap apart from the inlet port, wherein

the cap unit does not move at the second position while being biased by the biasing unit, and

the cap unit includes a pair of ridges that protrude in directions toward both outer sides from the center in a width direction and extend in a longitudinal direction of the cap unit.

2 . The recording apparatus according to claim 1 , wherein

in a case where the cap unit is at the first position, the cap unit maintains the first position with a self-weight of the cap unit opposing biasing by the biasing unit.

3 . The recording apparatus according to claim 1 , wherein

in a case where the cap unit is at the first position, a combined moment obtained by combining an biasing moment of a force to turn the cap unit by the biasing unit with respect to an axial center of the shaft portion and a self-weight moment of a force to turn the cap unit by the self-weight of the cap with respect to the axial center has a direction to turn the cap unit in a capping direction from the second position toward the first position, and

in a case where the cap unit is at the second position, the combined moment has a direction to turn the cap unit in an uncapping direction from the first position toward the second position.

4 . The recording apparatus according to claim 3 , wherein

as the cap unit turns from the first position to the second position, the combined moment continuously changes from a first predetermined value having a direction to turn the cap unit in the capping direction to a second predetermined value having a direction to turn the cap unit in the uncapping direction.

5 . The recording apparatus according to claim 4 , wherein

as the cap unit turns from the first position to a predetermined position between the first position and the second position, the combined moment monotonically changes from the first predetermined value having the direction to turn the cap unit in the capping direction to a third predetermined value having a direction to turn the cap unit in the uncapping direction.

6 . The recording apparatus according to claim 3 , wherein

the cap unit stays at the first position with an equilibrium established between the combined moment and a moment of a contact force generated by contact of a first predetermined portion of the cap unit with a second predetermined portion of the housing, and

the cap unit stays at the second position with an equilibrium established between the combined moment and a moment of a contact force generated by contact of a third predetermined portion of the cap unit with a fourth predetermined portion of the housing.

7 . The recording apparatus according to claim 1 , wherein

the cap unit includes a lever and a cap loosely fitted in the lever,

the cap unit is supported by the housing rotatably about the shaft portion in such a way that a predetermined portion near a first end of the lever is aligned with the shaft portion,

the cap is arranged at a position shifted from a second end of the lever toward the first end of the lever by a predetermined distance, the second end being opposed to the first end, and

in a case where the cap unit is at the first position, the cap caps the inlet port.

8 . The recording apparatus according to claim 7 , wherein

a grip portion is provided to the second end of the lever.

9 . The recording apparatus according to claim 1 , wherein

the cap unit includes a cap-unit-side engagement portion that engages with a housing-side engagement portion in a case where the cap unit is at the first position.

10 . The recording apparatus according to claim 1 , wherein

in a case where the cap unit is at the first position, the pair of ridges included in the cap unit are held between a pair of ridges that are provided on both side surfaces of a recess of the housing in which the cap unit is housed and that protrude in directions from both outer sides toward the center in the width direction and extend in a turning direction of the cap unit.

11 . The recording apparatus according to claim 1 , wherein

the biasing unit is a tension spring.

12 . The recording apparatus according to claim 1 , further comprising:

a cover that is provided above the housing and the cap unit and is turnable between a closed position at which the cover covers the housing and the cap unit, and an opened position at which the cover allows the housing and the cap unit to be exposed; and

a recording head that executes printing on a recording medium with ink stored in the tank.

13 . The recording apparatus according to claim 12 , wherein

if the cap unit is located at a position shifted from the first position toward the second position in a case where the cover is turned from the opened position to the closed position, the cover comes into contact with the cap unit and pushes the cap unit until the cap unit is moved to a position close to the first position, thereby causing the cap unit to cap the inlet port.

14 . The recording apparatus according to claim 13 , wherein

the position close to the first position is a position at which a combined moment obtained by combining an biasing moment of a force to turn the cap unit by the biasing unit with respect to an axial center of the shaft portion and a self-weight moment of force to turn the cap unit by a self-weight with respect to the axial center has a direction to turn the cap unit in a capping direction from the second position toward the first position.